Esophageal biopsies in the management of GERD: Complementary tool for many but not for all

We read with great interest the study by Schneider and colleagues [1] that aimed to assess the clinical significance of microscopic esophagitis, defined according to the Esohisto project. The authors conducted a multicenter study involving 1071 individuals who underwent upper gastrointestinal endoscopy with various unselected indications. They proved the feasibility of the Esohisto consensus guidelines and concluded that esophageal biopsies should routinely be obtained in case of suspicion of gastroesophageal reflux disease (GERD). Firstly, we congratulate the authors for their study, in particular, for the high number of patients enrolled. Second, we would like to highlight that their results confirmed our previous findings obtained in studies aimed to correlate histology with a more robust diagnosis of GERD based on endoscopy and pH findings [2] and [3]. In particular, very recently, using the state-of-the-art technique to objectively assess GERD that is impedance-pH monitoring, we clearly identified patients with GERD (abnormal esophageal acid exposure and/or positive reflux symptom association) from those without GERD (functional heartburn patients: normal esophageal acid exposure and negative reflux symptom association) [3] and [4]. Thereafter, we demonstrated that severity and prevalence of microscopic esophagitis increased in parallel with the severity of GERD and was helpful in distinguishing healthy subjects and patients with functional heartburn from those with GERD [3]. Nevertheless, microscopic esophagitis was observed in 15% (3/20) of controls, suggesting the lack of high specificity of these markers and the importance of combining histology with combined multichannel intraluminal impedance and pH monitoring. We also found microscopic lesions in subjects with negative endoscopy and impedance-pH monitoring but with GERD symptoms assessed by means of a validated questionnaire, allowing an objective diagnosis in more than half of functional heartburn cases [3]. It is relevant to note that in our studies the combined severity score was assessed by obtaining 2 biopsies across the Z line and 2 at 2 cm above it, whereas Schneider et al [1] adopted a different biopsy protocol: 2 biopsies taken from the gastric folders below the Z line and 2 at 1 cm above it. This seems to be important in order to limit the lower specificity and sensitivity that proximal and distal histologic samples tend to provide, respectively, and to reduce the variability related to the patchy distribution of the microscopic lesions indicative of microscopic esophagitis. Although the biopsy protocol adopted by the authors could be characterized by a lower sensitivity, they further provided the clinical validation, so far missing, of the Esohisto consensus guideline [5]. In conclusion, the study by Schneider et al [1] confirms the potential role of histology in the work-up of GERD patients. However, we believe that esophageal biopsies should be limited to patients with nonerosive reflux disease, especially in those refractory to antisecretory treatments, in order to contribute to the use of esophageal functional testing (pH-metry or impedance-pH testing) for the final diagnosis GERD. Routinely histology can be omitted in patients with erosive esophagitis, since it does not add any information.